Obama on the Gulf oil spill: 'My job is to get this fixed'

Under pressure to step up his response to the Gulf of Mexico oil spill, President Barack Obama tried to assure the country Thursday that he and his administration are in charge and working feverishly to clean up the mess. The U.S. Geological Survey said new estimates show as many as 25,000 barrels of oil rushing into the Gulf waters each day, or as much as five times oil giant BP’s original estimate of 5,000 barrels a day.

WASHINGTON — Under pressure to step up his response to the Gulf of Mexico oil spill, President Barack Obama tried to assure the country Thursday that he and his administration are in charge and working feverishly to clean up the mess.

"My job is to get this fixed," Obama said a day before leaving for his second tour of the Gulf since an April 20 oil rig explosion triggered what's now acknowledged to be the worst spill in the nation's history.

"I take responsibility. It is my job to make sure that everything is done to shut this down. . . . The federal government is fully engaged. And I'm fully engaged."

Scientists Thursday declared the five-week-old BP spill in the Gulf of Mexico to be the worst in U.S. history, and federal and oil industry officials capped a day of confusion by announcing that they'd suspended and then restarted their mud-pumping "top kill" procedure to plug the well.

BP's operating chief disclosed that engineers had not pumped any mud into the runaway oil and gas spill since the night before.

On Thursday night, the Coast Guard announced that BP had resumed pumping mud in an effort to plug the leak. A 10-hour burst of 15,000 barrels of mud on Wednesday slowed the spill, said BP's Doug Suttles. However, engineers suspended it to replenish the mud back to its 50,000 barrel capability and review their procedures.

Thursday night's resumption might follow with a "junk shot" of "plating materials" and "dense rubber balls" to plug the leak.

The U.S. Geological Survey said new estimates show as many as 25,000 barrels of oil rushing into the Gulf waters each day, or as much as five times energy giant BP's original estimate of 5,000 barrels a day. At the new rate, nearly 38 million gallons of crude oil is polluting gulf waters, killing animals and threatening fragile marshlands.

USGS director Marcia McNutt cautioned that the numbers were all preliminary and "highly dynamic." The scientists and engineers on the team are getting new data and "will continue to refine and update the estimate," she said.

Even if the effort to seal the leak works, the cleanup took on new urgency as researchers from the University of South Florida said they'd discovered a big, previously undetected plume of oil underwater about 22 miles south of Mobile, Ala.

While hoping that the top kill would finally stop the leak at the ocean floor, Obama said he'd use his visit to the region Friday to discuss stepped-up efforts by the federal, state and local governments to protect the Gulf coast or clean up oil that's already washed ashore.

"Our concern regarding these contaminants is they have the potential to be incorporated in the food web," said David Hollander, a chemical oceanographer who's a lead investigator in the research mission. "The first ecological impact of this spill is the effect on coastal habitats, including marshes, beaches and estuaries. The second threat to nature would be the impact on the food webs. That is what's at risk."

"This manmade disaster is now the largest oil spill in our nation's history, topping the Exxon Valdez by twice as much," said Rep. Ileana Ros-Lehtinen, R-Fla., referring to the 1989 tanker spill in Alaska's Prince William Sound. "The federal government needs to step up to the plate and demonstrate the leadership that BP has failed to show. I am hopeful the 'top kill' operation will bear fruit, but the ecological and economic damage has been done, and there is no turning back from that."

With a preliminary report on the oil spill in hand, Obama announced several interim steps:

Suspending planned exploratory drilling in the Arctic Ocean off of Alaska until at least 2011

Canceling a pending lease sale in the Gulf of Mexico and a proposed lease sale off the Virginia coast

Continuing an existing moratorium on any new offshore drilling and suspending the issuance of new deepwater well permits for six months

Suspending action on 33 deepwater exploratory wells being drilled in the Gulf of Mexico

Interior Secretary Ken Salazar said the actions wouldn't hurt the country's immediate need for oil and natural gas, noting that 591 deepwater wells and 4,515 shallow water wells in the gulf will continue to pump oil and gas.

However, he also told reporters he made a mistake when he recommended this spring that the government could safely open new offshore areas to drilling, a proposal Obama has now suspended until the gulf spill is fully studied.

"The assumption I made was that these activities could go forward in a safe way . . . that assumption obviously was an assumption that was mistaken," Salazar said.

In his press conference, Obama insisted anew that he and his administration have been responding aggressively, striving to reject complaints that he should have acted more forcefully, or that the federal government is giving BP too much freedom to fight the spill and organize the clean-up.

"The American people should know that from the moment this disaster began, the federal government has been in charge of the response effort," he said.

He said the government has always had final say over what BP is doing. He noted, for example, that when BP said it would start drilling a relief well, the government ordered it to drill two simultaneously as a precaution.

"Make no mistake, BP is operating at our direction. Every key decision and action they take must be approved by us in advance," Obama said.

However, he acknowledged under questioning that the plans for a massive oil spill were inadequate and that his own Interior Department hadn't made sufficient progress in cleaning up its Minerals Management Service, which oversees oil drilling.

The director of that agency, Elizabeth Birnbaum, resigned Thursday. Rep. Ros-Lehtinen called it an overdue dismissal, though Birnbaum, who'd held the job less than a year, took over after the period criticized in the report, and Salazar called the resignation voluntary.

Obama said the government is still rushing in the booms used to stop oil on the surface, despite his insistence that it had prepared for a worst-case scenario from the first day.

"When it comes to the response since the crisis happened, I am very confident that the federal government has acted consistently with a sense of urgency," he said. "Prior to this accident happening, I think there was a lack of anticipating what the worst- case scenarios would be, and that's a problem."

(Erika Bolstad and Margaret Talev contributed to this article from Washington. Carol Rosenberg of the Miami Herald contributed from Miami.)